Dual subs time aligned and eq'd but nothing from standmount or subs at 80hz to 100 hz in that corner!! Anything I can do other than move?
View attachment 125289
View attachment 125289
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Am I screwed??? 80-100 hertz is non existent with this configuration..happy wife happy....er life.
- Thread starter Nwickliff
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You have a non-existent attachment, too.
Works now, though...
- Thread Starter
- #4
Should be good
Pdxwayne
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You already used REW to do frequency sweep?
For example:
Just speakers?
Speakers + Subs?
One sub is about 7 feet away from your corner, the other 14 feet.
At some frequency the direct waves will be out of phase... cancellation.
80 Hz has a 14 foot wavelength, half of that is seven feet, so, looks like they cancel around that frequency to me.
http://www.mcsquared.com/wavelength.htm
(the above does not take the effect of the rest of the room into account)
Experiment with the timing?
I have a hole around 48Hz at the listening position, even with symmetrical speaker position, because the back of the room is open on one side,.
I can get rid of it by notching the output of one channel and boosting the other.
However, I don't sit in a corner, and haven't contemplated that arrangement.
At some frequency the direct waves will be out of phase... cancellation.
80 Hz has a 14 foot wavelength, half of that is seven feet, so, looks like they cancel around that frequency to me.
http://www.mcsquared.com/wavelength.htm
(the above does not take the effect of the rest of the room into account)
Experiment with the timing?
I have a hole around 48Hz at the listening position, even with symmetrical speaker position, because the back of the room is open on one side,.
I can get rid of it by notching the output of one channel and boosting the other.
However, I don't sit in a corner, and haven't contemplated that arrangement.
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Izzit possible to move the sub pictured at the bottom farther along the same wall? Perhaps near the window?
What sort of bass response can you generate, with a single sub.
What sort of bass response can you generate, with a single sub.
- Thread Starter
- #8
Going to try that now. Thanks.
- Thread Starter
- #9
Going to try that now. Thanks. As soon as I posted and looked at my setup again I was thinking about those subs not being equidistant. Even if I got cancelations but closer to 100hz or so, I would be happier since that's where I cross to mains.
audiofooled
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https://amcoustics.com/tools/amroc?l=27&w=18&h=8&ft=true&r60=0.6
It may very well be that you have room mode issues at the listening position, resulting in cancellation at those particular frequencies. There are other calculators, but if you use this simple one and enter correct room dimensions you can easily get the picture. Even though you should take the calculations with the grain of salt, AFAIK, any corner of any room is rarely a good listening position because many of the modes accumulate there. The Bolt area that this and other calculators suggest for a good listening position almost never includes any of the corners. I hope this helps.
It may very well be that you have room mode issues at the listening position, resulting in cancellation at those particular frequencies. There are other calculators, but if you use this simple one and enter correct room dimensions you can easily get the picture. Even though you should take the calculations with the grain of salt, AFAIK, any corner of any room is rarely a good listening position because many of the modes accumulate there. The Bolt area that this and other calculators suggest for a good listening position almost never includes any of the corners. I hope this helps.
astr0b0y
Active Member
What are you using to combine the sub's responses? I'd try playing with delays/phase settings methodically and measuring. Long process though.
Hipper
Addicted to Fun and Learning
What crossover region are you using for subs/main speaker?
- Thread Starter
- #14
Thank you. I think this is the hard truth. Both the mains and subs have nulls there and I've tried moving the subs basically everywhere against the wall.
not really possible unfortunately
I've tried 80 and 90. Problem is mains have the same null so my only option was to get the subs to play through 80-90hz. Almos like having two drivers that don't extend all the way to the XO which means there's nothing you can really do except use different drivers or add a filler driver.XO has to be 80-90hz because mains have the same dip in the room at 80-90hz.
Pdxwayne
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How about just try one sub and try with differwnt phase of the sub? I recently used REW to match my sub to my speakers in my computer room setup and phase of 0 vs 180 makes a difference.Thank you. I think this is the hard truth. Both the mains and subs have nulls there and I've tried moving the subs basically everywhere against the wall.
not really possible unfortunately
XO has to be 80-90hz because mains have the same dip in the room at 80-90hz.
Also, have you tried listening far away, in your other seats at the top right of your drawing? Or, walk around the room and find the best location for frequency evenness?
- Thread Starter
- #16
Ok, this is a mains problem not a sub problem. The real dip is at 100hz or 90-130hz. Yikes. I tried moving the standmounts to the floor to see if having the woofer nearer to the floor would fill that gap and it definitely helped. So perhaps towers with bass drivers closer to the floor would solve this issue. 
Pdxwayne
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I see that both subs by themselves looks OK. It is when you add in the speakers you have issue.
You may have to totally give up eq both subs together independent of matching to mains.
Have you tried independently matching right sub to right speaker and left sub to left speaker?
I did that with REW when I was using twin subs and I was really surprised that I needed to use totally opposite phase setting for my subs. Still sounded great.
Hipper
Addicted to Fun and Learning
That appears to be quite wide and 12dB deep. With 'no smoothing' it will look worse still.
Bearing in mind your experiments with your speakers on the ground, could you measure what happens if you put your subs next to the speakers, either inside or outside them, or even underneath them?
Even though you don't want to move the seat out from the corner, measure as if you could: i.e. bring the mic out towards your speakers? See what that does.
Another thing you could do is play a 103Hz test tone, then move around your listening position, sideways, up and down, to hear if that sound gets louder or quieter. You can get some bass test tones here:
http://realtraps.com/test-cd.htm
Surely you have some scope for moving your main speakers? For instance you could place them right next to the TV.
Bearing in mind your experiments with your speakers on the ground, could you measure what happens if you put your subs next to the speakers, either inside or outside them, or even underneath them?
Even though you don't want to move the seat out from the corner, measure as if you could: i.e. bring the mic out towards your speakers? See what that does.
Another thing you could do is play a 103Hz test tone, then move around your listening position, sideways, up and down, to hear if that sound gets louder or quieter. You can get some bass test tones here:
http://realtraps.com/test-cd.htm
Surely you have some scope for moving your main speakers? For instance you could place them right next to the TV.
Could you co locate the subs and mains , this way you could run the subs further up the frequency spectrum without localisation isssue .. or stack the subs as that might help too.
- Thread Starter
- #20
This is interesting. I might give this a shot. I think I accidentally set my XO to 80 when it needed to be 90hz for the mains plus sub sweep which made the gap larger. The lowest dip there is at 100hz which I don't want the subs to play anyway or I'll be able to localize them during playback especially all the way up to 140hz where the gap ends. I also forgot to adjust the alignment with mains since I adjusted the alignment between subs.
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